This application claims the benefit of Korean Patent Application No. 2001-45256, filed Jul. 26, 2001, the disclosure of which is hereby incorporated herein by reference in its entirety as if set forth fully herein.
The present invention relates to integrated circuit devices and operating methods, and more particularly to integrated circuit voltage generating circuits and methods.
Integrated circuit devices are widely used in consumer and commercial applications. Many integrated circuit devices, such as integrated circuit memory devices, employ a high voltage and a low voltage in the integrated circuit, which are generated in the integrated circuit from one or more power supply voltages that are provided to the integrated circuit. For example, many integrated circuit devices include a high voltage generating circuit, which generates a high voltage and a low voltage generating circuit, which generates a low voltage. See, for example, U.S. Pat. Nos. 6,052,022 and 5,796,293 that are assigned to the assignee of the present application, the disclosures of which are hereby incorporated herein by reference in their entirety as if set forth fully herein. A first pumping capacitor may be used for pumping the high voltage and a second, separate pumping capacitor may be used for pumping the low voltage.
FIG. 1 is a block diagram illustrating a conventional voltage generating circuit. The voltage generating circuit of FIG. 1 separately includes a high voltage control signal generating circuit 10, a high voltage generating circuit 12, a low voltage control signal generating circuit 20, and a low voltage generating circuit 22.
The high voltage control signal generating circuit 10 generates a high voltage control signal VPPEN in response to a high voltage enable signal VPEN. The high voltage generating circuit 12 generates a high voltage VPP in response to the high voltage control signal VPPEN. The low voltage control signal generating circuit 20 generates a low voltage control signal VBBEN in response to a low voltage enable signal VBEN. The low voltage generating circuit 22 generates a low voltage VBB in response to the low voltage control signal VBBEN.
The conventional voltage generating circuit of FIG. 1 includes the high voltage generating circuit and the low voltage generating circuit which are separately configured. Even though not shown, separate pumping capacitors are configured in the high voltage generating circuit and the low voltage generating circuit, respectively.
Some embodiments of the present invention provide integrated circuit voltage generating circuits that include an integrated circuit substrate, a first voltage generating circuit in the integrated substrate that is configured to generate a first voltage from a power supply voltage, and a second voltage generating circuit in the integrated circuit substrate that is configured to generate a second voltage that is different from the first voltage from the power supply voltage. A shared capacitor in the integrated circuit substrate is connected to both the first voltage generating circuit and to the second voltage generating circuit. The shared capacitor, also referred to as a pumping capacitor or a shared pumping capacitor, is used by the first voltage generating circuit and the second voltage generating circuit, to generate the first and second voltages, respectively. Accordingly, in some embodiments of the present invention, the layout area of an integrated circuit voltage generating circuit in an integrated circuit substrate may be reduced by sharing a pumping capacitor by the first and second voltage generating circuits.
In some embodiments of the present invention, the first voltage generating circuit includes a plurality of capacitors and the shared capacitor is of larger capacitance than any of the plurality of capacitors. In other embodiments, the first voltage generating circuit includes a first transistor and generates the first voltage at a first node. The second voltage generating circuit includes a second transistor and generates the second voltage at a second node. The first transistor, the shared capacitor and the second transistor are serially connected between the first node and the second node. In yet other embodiments, the first voltage is of opposite polarity than the power supply voltage and the second voltage is of same polarity as, but greater than, the power supply voltage. In still other embodiments, the first voltage and second voltage are used with a memory cell array in the integrated circuit substrate. The memory cell array operates from the power supply voltage, the first voltage and the second voltage.
Other embodiments of the present invention provide a voltage generating circuit, comprising: control signal generating means for generating high and low voltage control signals for interleavingly toggling high and low enable signals when the high and the low voltages are all enabled, for generating the high voltage control signal for toggling the high voltage enable signal when the high voltage enable signal is enabled, and for generating the low voltage control signal for toggling the low voltage enable signal when the low voltage enable signal is enabled. Voltage generating means also is provided for pre-charging high and low voltage pumping nodes during a pre-charge operation in response to the high and the low voltage control signals, respectively, for pumping a pumping capacitor connected between the high and the low pumping nodes to generate a low voltage during a low voltage generating operation in response to the low voltage control signal, and for pumping the pumping capacitor to generate a high voltage during a high voltage generating operation in response to the high voltage control signal.
Other voltage generating circuits according to other embodiments of the invention include control signal generating means for generating high and low voltage control signals for interleavingly toggling high and low voltage enable signals when the high and the low voltage enable signals are all enabled, for generating the high voltage control signal for toggling the high voltage enable signal when the high voltage enable signal is enabled, and for generating the low voltage control signal for toggling the low voltage enable signal when the low voltage enable signal is enabled. Low voltage control means also is included for generating a low voltage generating control signal to a low voltage generating control node in response to the high voltage control signal and for generating first and second pre-charge control signals respectively applied to first and second pre-charge nodes by combining the high and the low voltage control signals. High voltage control means also is included for generating a high voltage generating control signal to a high voltage generating control node in response to the low voltage control signal and for generating third and fourth pre-charge control signals respectively applied to third and fourth pre-charge nodes by combining the high and the low voltage control signals. Low voltage generating means is provided for pre-charging the low voltage pumping node in response to the first and the second pre-charge control signals during the pre-charge operation, for transmitting a voltage of the low voltage pumping node to a low voltage generating terminal in response to the low voltage control signal during the low voltage generating operation, and for pumping the high voltage by pumping the pumping capacitor in response to the low voltage control signal during the high voltage generating operation. Finally, a high voltage generating means is included for pre-charging the high voltage pumping node in response to the third and the fourth pre-charge control signals during the pre-charge operation, for transmitting a voltage of the high voltage pumping node to a high voltage generating terminal in response to the high voltage control signal during the high voltage generating operation, and for pumping the low voltage by pumping the pumping capacitor in response to the high voltage control signal during the low voltage generating operation.
Other embodiments of the present invention provide voltage generating methods. A high voltage pumping node is stepped up by pumping a pumping capacitor connected between the high voltage pumping node and a low voltage pumping node in response to a high voltage control signal during a high voltage generating operation. The high and the low voltage pumping nodes, respectively, are pre-charged during a pre-charge operation. A voltage of the low voltage pumping node is stepped down by pumping the pumping capacitor in response to a low voltage control signal during a low voltage generating operation. A voltage of the low voltage pumping node is transmitted to a low voltage generating terminal.
Other voltage generating methods, according to embodiments of the invention, step up a voltage of a high voltage pumping node by pumping a pumping capacitor connected between the high voltage pumping node and a low voltage pumping node in response to a high voltage control signal during a high voltage generating operation, and transmit the voltage of the high voltage pumping node to a high voltage generating terminal. The high and the low voltage pumping nodes, respectively, are pre-charged during a pre-charge operation. The stepping and pre-charging are performed repeatedly.
Still other voltage generating methods, according to embodiments of the invention, comprise stepping down a voltage of the low voltage pumping node by pumping the pumping capacitor in response to a low voltage control signal during a low voltage generating operation, and transmitting a voltage of the low voltage pumping node to a low voltage generating terminal. The high and the low voltage pumping nodes, respectively, are pre-charged during a pre-charge operation. The stepping and pre-charging are performed repeatedly.